he grand experiment is over, and it’s a success. The first 22 films of the Marvel Cinematic Universe comprise a saga similar to a TV serial, but with way more characters, way more side journeys and way more money. And most remarkably for a movie series, it has an ending for the initial batch of six Avengers, with “Avengers: Endgame.” We knew all this going into the film, which itself raises one final question: Does it stick the landing? The answer is a qualified yes.

(Spoilers follow.)

“Endgame” ultimately delivers amazing final moments for Tony/Iron Man (Robert Downey Jr.) and Steve/Captain America (Chris Evans). By the end of its third hour, it has climbed all the way back from an opening 60 to 90 minutes that aren’t exactly boring, but are definitely meandering. It feels like we’re watching a Blu-ray Ultimate Edition in the theater, with all the deleted scenes restored. There’s a whiff of ego as the MCU’s big four creators (writers Christopher Markus and Stephen McFeely and directors Anthony Russo and Joe Russo) wallow in scene after scene of the heroes who survived Thanos’ (Josh Brolin) Snap in “Infinity War” being depressed as hell over the loss of their friends.

By the end of its third hour, it has climbed all the way back from an opening 60 to 90 minutes that aren’t exactly boring, but are definitely meandering. It feels like we’re watching a Blu-ray Ultimate Edition in the theater, with all the deleted scenes restored.

As my mind wandered, I recalled reading that one of the creators said “Endgame” is 3 hours long because that’s how long it needs to be. That’s not remotely true. A better cut of this film could’ve been crafted at 2.5 hours.

That said, the wallowing is actually the best part of the film’s first half, because the plot advancement is mumbo-jumbo about time travel. Tony and Bruce/Hulk (Mark Ruffalo), with some assistance from Scott/Ant-Man (Paul Rudd), theorize how to travel through time, then test it a few times with Ant-Man’s suits. Then a bigger time machine is suddenly on screen even though we haven’t seen it get built, and it seems they only need their suits anyway.

But whatever. Once our heroes do travel through time, “Endgame” gets good. If you showed up 90 minutes late, you luckily picked the first movie in history where you can miss the first 90 minutes and not be lost. When that “New York, 2012” hits the screen in huge letters, we are finally off and running.

It used to be a novelty when films or TV give alternate perspectives on classic scenes, or when they de-age actors for scenes set in the past (a trick that’s almost entirely the property of the MCU), or when a character fights “himself”/“herself.” “Endgame” uses all those tricks so smoothly that we don’t think about them anymore, and it uses them to great storytelling effect. The only way this stuff would be cooler is if we rewatched “Avengers,”“Thor: The Dark World,” etc., and realized that in the background, these scenes from “Endgame” have been there all along. (Franchise overseer Kevin Feige is always on the ball, but even he didn’t plan things out that well.)

Traveling into the past also allows for neat return engagements that the marketing team wisely and successfully kept under wraps, such as Natalie Portman – who it seemed was done with this superhero stuff – popping in as Jane, the ex-girlfriend of Thor (Chris Hemsworth). It’s a small moment – so small it might’ve been culled from unused “Dark World” footage – but important for emphasizing the continuity of these 22 films.

I would’ve never guessed this beforehand, but Nebula (Karen Gillan) of all people has the best arc of “Endgame.” Caught between her desire to please her father, Thanos, and seeing the person her future self has become, Nebula’s internal conflict is engaging, and in sync with the plot. She’s not the only one whose personal choice is pivotal to the galactic stakes; it’s impressive how many heroes need to make the correct decision at a key point for the overall plan to work. I also like how “Endgame” carves out a nice friendship story for non-superpowered Clint/Hawkeye (Jeremy Renner) and Natasha/Black Widow (Scarlett Johansson).

On the other end of the power meter is Captain Marvel (Brie Larson), whose one weakness is that she can’t be in two places at once. All snark aside, she does have a line that tidily addresses this: Other planets are also going through the post-Snap pain, and those other planets don’t have the Avengers, so she’s needed there more so than on Earth.

Once we’re fully in the endgame, we get one of those almost hilariously epic comic-book battles – featuring every major hero – brought to stunning life. Cynically speaking, comic-book writers and artists draw these battles because they can (a comic’s “special effects budget” is unlimited). But as successful as the MCU movies have been, their special effects budget is almost unlimited too, and the finale of “Endgame” is the collective imaginations of Stan Lee and the other Marvel legends dumped onto a screen instead of a page. The music by Alan Silvestri makes for delicious enhancement of the action.

What’s especially impressive is that this grand battle is so gripping; it’s not incomprehensible sound and fury. And when the camera zooms in on a specific hero – giving them their “panel” – we feel what this moment means for that hero; it’s not merely the superhero version of the announcement of a baseball all-star game lineup.

The fact that heroes can pop into this film for a few seconds and make us care means “Endgame” is building on what came before. It’s tempting to praise this movie to the moon because it remembers all of its “War and Peace”-sized cast of superheroes. These 3 hours of the MCU, though, aren’t its elite 3 hours. This film takes forever to get going, the time-travel science is technobabble, and all but the most studious fan will need to check out one of those “‘Avengers: Endgame,’ Explained” videos on YouTube to grasp it all.

The “Endgame” part of “Avengers: Endgame” is glorious spectacle with messy plotting. It’s the “Avengers” part that really clicks: These six heroes – even the two who aren’t “super” — make a heckuva team, and this film regularly reminds us why they do.